Another Secret
by glitter-and-tails
Summary: <html><head></head>Mephisto suspects that Rin will hit demon puberty at any moment. This means that Rin will have 'demonic urges.' Yukio helps Rin suppress them by making a potion for him to drink every morning. What happens when Rin is out of potion and has to go to school? Cover art isn't mine. ShimaxRin, yaoi, rated M for sexy times.</html>


**Hello fello fanfic readers and writers! I'm new to publishing stories, but I'm not new to writing! I can't gaurantee that I'll be updating regularly everytime since life and, fuck my life (and pardonnez mon français), school happens sometimes. **

**As soon as I started watching Blue Exorcist, I instantly shipped Shima and Rin. I was pleasantly surprised by all the art and fanfic that came with the ship! But they're both so cute, it only makes sense right? RIGHT?! So I decided to contribute and hopefully expand the fandom. Because honestly people need realize that these cuties are perfect. I haven't read the manga (though I've heard some crazy spoilers), so I don't know how their characters develop later on.**

**Anyway, I don't own the characters aaand enjoy!  
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><p>Rin was trying hard to concentrate on Yukio's lecture, but the monotony of his voice made his brain fuzzy. Just as he thought he was going to lose the battle, Yukio started to wrap up the lesson on the development of sin from demon to human. What does this have to do with becoming an exorcist?<p>

"Nii-san!" Yukio called. Rin, sure he was in trouble for zoning out, pouted as he looked up at his brother. But Yukio just smiled indulgently at him. "You're not in trouble. This time."

Rin perked up a little as he pushed happily off his chair toward his brother. Shima raised an eyebrow at him as the class started out of the room, but Rin just shrugged. Shima shook his in feigned disappointment even though Yukio said he hadn't done anything wrong.

"If I'm not in trouble, what is it?" Rin leaned in toward Yukio eagerly. "It's not a mission, is it? You have to tell me if it is!" he pushed excitedly, and Yukio pushed his glasses up to hide some of his annoyance. Yukio was probably resisting the urge to point out Rin's immaturity, but Rin was too pumped to care.

He walked over to the other side of his desk to dig through one of his many drawers. Yukio was such a tease! Rin's tail began to twitch impatiently when he clunked a small briefcase onto his desk. Rin reached for it with round, child-like eyes, but Yukio slapped his hand away.

"You have to be careful," he told Rin as he looked him straight in the eyes. Rin saw the hardness in his eyes and tension in the set of his jaw. Suddenly, Rin felt a sense of foreboding. He realized that, while he wasn't in trouble, this after-class 'surprise' might not be a good thing.

"What is it?" Rin pressed his brother nervously. Yukio unlatched the case and carefully took out a clear vial of blue liquid. Little pieces of plants and other suspicious looking substances were floating in it. Rin gulped. "What… is it?" he repeated feebly.

"Rin, you're a half-demon who's inherited demonic powers, so it's only logical that you have demonic… urges" he explained hesitantly. "You obviously have temperamental issues-" Rin opened his mouth angrily, but Yukio continued with new determination clear in his voice. "But more importantly, demons need to mate in order to live without constant agony."

He tried to sound scholarly, but Rin saw him flinch slightly. His brother was worried about him, and that thought alone gave Rin the courage not to demon out. He did have an old-fashioned panic attack though because he felt like he had some rights.

"I have to mate as in have sex? With who? Or should I say what?" he shouted hysterically. Yukio tried to speak, but Rin was just getting started.

"I may be a demon, but I still have standards! In case you haven't noticed, I am one helluva virgin!" As he said that, his hysteria turned into panic. Who would want to have sex with him? His classmates were just starting to accept him as Satan's son.

Yukio saw his opening and caught Rin's attention by shoving the small vial in his hand. "And that is why I made you this. Drink a vial every morning, and you should be fine. I just wanted you to start drinking this before you experience symptoms. Mephisto said you're due any day now," he added grimly.

Rin stared wonderingly at the small vial cool against his palm as he walked slowly to the dorm he shared with Yukio. A lot of his classmates tried to catch his attention, but he was too wrapped up in his thoughts to notice.

This… concoction looked really suspicious. Rin knew Yukio wouldn't do anything to it, but he didn't know how much Mephisto was involved. Mephisto always had a private agenda, and Rin didn't trust that clown of a principal one bit.

When Rin got back to his dorm, he could already smell Ukobach's cooking. Rin rounded into the kitchen quickly, half curious and half ravenous. His ears twitched excitedly when he saw his pink-haired friend stuffing his face with Ukobach's latest creation.

"Yo Rin," Shima mumbled while trying to stuff more food in his mouth. Rin wrinkled his nose, disgusted and jealous at the same time and plunked down on the chair across from Shima with a dramatic sigh.

Shima caught on to Rin's not-so-subtle hints and dropped his fork into his half-empty bowl of deliciously smelling noodles. He propped his chin up on his hand and rested his elbow casually onto the table. "Did Yukio punish you for something?" he asked.

Rin leaned over, and Shima eagerly followed suit. When Rin could smell the snack on Shima's breath, he paused. "Promise not to tell anyone? Especially Bon?" Rin asked nervously.

Shima nodded quickly at Rin with round eyes. His silence told Rin to hurry up, but Rin wasn't sure how to explain it. "Yukio told me I'm going to want sex very badly since I'm growing up as a half-demon" Rin said slowly and waited for that to sink in.

When Shima just stared dumbfounded at him, Rin started talking in a rush. "I won't have to worry about it though if I take this potion Yukio made for me. I'll be fine and everything stays normal, but…," Rin trailed off with a sigh.

"But what?" Shima interjected. Rin jumped at how close his face was to his and tried to push down the rush of heat rushing up his neck. Rin tried to find anything negative in Shima's brown eyes, but they only held warmth.

Rin slumped back into his chair, finding it easier to breathe and watch Shima's reactions from a greater distance. "I don't know. It's just scary to think about, and I'm afraid Mephisto might be up to something," Rin admitted sheepishly.

Shima's face was unreadable for several seconds. Then his signature smile spread across his face. Rin boiled at his amusement, and his tail thumped the table angrily. "It's not funny!" he said angrily.

Shima looked momentarily distracted by his tail but looked quickly back at Rin with a serious expression. "It kind of is," Shima pointed out, "but that's not why I was smiling. I was smiling because you'll be fine either way."

Rin blinked at Shima in disbelief at what he had just said. He'll be fine either way? "What's that supposed to mean?" he growled.

"It means Yukio would never give you anything potentially harmful, and you've got people who care about you," Shima said simply. "No one would let you suffer, not Shiemi, me, or even Bon. Whatever you decide will work out."

All Rin could think was that Shima said Rin's life was more important than his own virtue. He felt unexpected warmth for his friend. Maybe Shima was right. He could wait until he noticed any signs and put his trust in Yukio's potion when he did. He was just overreacting to a confusing situation. His tail brushed across the table subconsciously as he thought about the situation.

Rin gasped when cool fingers carefully encircled his tail and immediately went still. Shima was holding it with curiosity in his eyes, completely unaware of the butterflies that erupted in Rin's stomach. "Your tail is so interesting. Does it feel like any other part of your body? Like another arm?" Shima asked innocently.

Rin was so distracted by the fingers now stroking his tail and burying into the fur that he could only manage to shake his head. Shima was focused on Rin's tail, so he didn't see him shaking his head. "Rin?" he asked as he looked up. His face was flaming red against the cool blue of his hair. He was biting firmly on his lower lip with one of his sharp fangs to suppress a groan. Tingles were traveling from the tip of the tail to his lower stomach.

Shima's hand was still carelessly petting Rin's tail, oblivious to why Rin was acting so off until he started visibly squirming. He quickly pulled his hand away as his face grew redder than Rin's from embarrassment. "S-sorry, I didn't know it was like that," he apologized weakly.

"S'okay" Rin mumbled. "I need to start my homework before Yukio catches me 'lazing off,' so you should head back." He managed to say all this while staring intently at the speck of food on the collar of Shima's white button-down.

Shima looked like he wanted to say something but eventually nodded nervously. Rin held his breath and watched as Shima walked toward the door. Before he could pretend he wasn't looking, Shima turned around to face him. "Remember that no matter what, we'll be there to help." He smiled sadly and walked away without another word.

As soon as he left, Rin took out the vial of blue liquid with shaking hands. The uncomfortable straining in his pants told him everything he needed to know. He had to drink it, or he would go crazy. Not letting himself change his mind, he opened the vial and clumsily gulped down the bitter potion. 

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><p><strong>Did you like it, hate it? Feel like stabbing something? Had a bad day? Like, follow, and review because that always cheers me up!<strong>


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